Cam type latch



' July 2s, 1959 Y. w. EHRET Y 2,896,989

CAM TYPE LATCH Filed oct. 2, 1957 t United Statcs Patent O CAM TYPELATCH Yale W. Ehret, Elkhart, Ind., assignor to The Adlake Company,Elkhart, Ind., a corporation of Illinois Application October 2, '1957,Serial No. 687,681

2 Claims. (Cl. 292-114) This invention relates to a' window latchconstruction and is more particularly concerned with improvements in alatch structure for tightly locking together a pair of window sashes,one of which is slidable relative to the other.

It is the general object of the invention to provide a latch or lockstructure for use on a sliding sash window which is of relatively simpleyet sturdy construction, which is highly efficient in operation, whichmay be easily installed on a window, which is very economical toproduce, and which will withstand considerable abuse.

without requiring repair of replacement.

lt is a further object of the invention to provide an improved cam typelatch construction for a pair of abutting window'sashes including acompressible sealing gasket secured to the closing edge of at least oneof the sashes, which latch acts to lock the s ashes tightly together toprovide an effective seal against drafts, rain, snow, etc.

It is a more specific object of the invention to provide a latchstructure for a sliding sash window including a keeper pin mountedadjacent an abutting edge of one of the sashes and a latch assemblymounted adjacent the abutting edge of the other sash, the latch assemblyincluding a cylindrical bushing eccentrically rotatable on the othersash, an elongated latch member rotatably mounted on the bushing andadapted to be pivoted into engagement with the keeper pin, and a leversecured to the bushings for pivoting the bushing from a releasedposition to a locking position while the latch member is in engagementwith the keeper pin, the eccentric mounting of the bushing acting toshift the latch member toward the latch assembly during rotation of thebushing to securely draw the sashes together and lock them tightly.

These and other objects and advantages of the invention will be apparentfrom a consideration of the window latch structure which is shown by wayof illustration in the accompanying drawings wherein:

Fig. l is a fragmentary elevational View of a pair of slidable abuttingsash members including a compressible sealing gasket on one of theabutting edges and showing the sashes in slightly open positions and thelatch device with the latch member and the locking lever in releasedpositions;

Fig. 2 is a view similar to Fig. l showing the sashes closed and thelatch member in its engaged position and the locking lever in itsreleased position;

Fig. 3 is a View similar toFigs. l and 2 showing the latch member in itsengaged position and the locking lever in its locking position;

Fig. 4 is a vertical sectional view taken generally along line 4 4 ofFig. 3;

Fig. 5 is a vertical sectional view taken generally along line 5-5 ofFig. 3; and

Fig. 6 is an enlarged vertical sectional view'of the latch assembly asshown in Fig. 5.

Referring to the drawings, there is illustrated a fragrnentary portionof a double sash slidable window conlce struction including a pair ofvertically disposed sashes 10 and 11 which are slidable in a horizontaldirection between open and closed positions. As best shown in Fig. 4, aresilient, compressible, rubber sealing gasket 12 is secured to theabutting edge of the sash 11, the sealing gasket 12 dovctailing with theabutting edge of the sash 10. The particular window shown in thedrawings is of the type that might well be found in the cab of a diesellocomotive and in such an installation the closed window must be verytightly sealed in order to keep out drafts, rain, snow, etc.

A preferred embodiment of a latch adapted to provide an effective sealin a window of this type is shown in the drawings and includes a keeperassembly 17 secured adjacent the abutting edge of the sash 10 and a 'jlatch assembly 18 secured adjacent the abutting edge 26. The mountingplate 25 is provided with an upstanding harige 27 extending partiallyalong the edge of the plate 25 farthest from the edge of the sash 11 tofacilitate manipulation of the sash 11 for sliding movement. A mountingpin 28 having an enlarged head portion 29 projects from the center ofthe plate 25 in horizontal alignment with the keeper pin 22 on the plate19.

As best shown in Figs. 5 and 6, a generally cylindrical bushing 35Vhaving a longitudinally extending bore 36 formed therein and offset withrespect to the axis of the bushing 35 is rotatably mounted on the pin28, the

bushing 35 being eccentrically rotatable thereon. An elongated latchmember or arm 39 has one end rotatably mounted on the bushing 35 and hasa hooked portion 40 at the other end adapted to engage the keeper pin22. An upturned flange 41 is provided on the hooked end of the latchmember 39 to facilitate rotation of the latch member 39 into and out ofengagement with the keeper pin 22.

Means are provided for rotating the bushing 35 relative to the pin 28 inthe form of a locking lever 42 overlying the latch member 39 and havingone end disposed about the bushing 35. The lever 42 is secured to thebushing 35, as by brazing at 44, Fig. 6, whereupon rotation of the lever42 through manipulation of a knob 43 on its free end causes eccentricrotation of the bushing 35 about the mounting pin 2S. To complete thelatch assembly 18, a washer 45 is disposed about the pin 28 between thebushing 35 and the mounting plate 25 and a resilient dished washer 46 isdisposed on the bushing 35 between the latch member 39 and the lever 42to maintain a slight frictional tightness in the operation of the latch.The bushing 35 is retained on the mounting pin 28 by the enlarged headportion 29 of the pin 28.

In Fig. l, the sashes 10 and 11 are shown in a slightly open positionand the latch member 39 and the locking lever 42 are shown in theirreleased positions. It is noted that in the released position of thelever 42, the axis and major body portion of the eccentrically mountedbushing 35 are disposed toward the abutting edge of the sash 1'1 withrespect to the mounting pin 28. To tightly lock the closed window sashestogether, the latch member 39 is first pivoted from its releasedposition, as shown in Fig. l, to its engaged position shown in Fig. 2wherein the hooked portion 40 is in engagement with the keeper pin 22.After the latch member 39 has been engaged With the keeper pin 22, thelever 42 is pivoted, counter-clockwise in the drawings, from itsreleased position, shown in Figs. 1 and 2, to its locking positionagainst the upturned flange 41 on the latch member 39, as shown in Fig.3.

It is noted that in Vrotating the lever 42 from its released position toits locking position, the bushing 35 has been rotated relatively to themounting pin 28 to a position wherein the axis and major body portion ofthe bushing 3S are disposed away from the abutting edge of the sash '11relative to the mounting pin 28. As the latch member 39 is rotatablycarried on the bushing 3S, this rotation'of the bushing 35 shifts thelatch member 39 toward the mounting pin 28 thus drawing the sashes 10and 11 toward each other and tightly locking them together. As shown bya comparison of Figs. 2 and 3, this locking action compresses thesealing gasket 12 and provides a very tight seal lwhich will eectivelykeep out` drafts, rain, snow, etc.

In the locking position of the lever member 42, as shown in Fig. 3, theaxis of the bushing 35 is disposed substantially in a plane passingthrough the axes of the keeper pin 22 and the mounting pin- 28 and onthe side orf the mounting pin 28 away from the keeper pin 22 to providea positive locking action. This cam type latch provides a very effectivelocking device and-preventsany unlatching of the window until thelocking lever 42 has been pivoted, clockwise in the drawings, to itsreleased position against the iiange 27 on the mounting plate 25.

While I have shown and described a preferred embodiment of my invention,it is to be understood that it is capable of many modifications. It isobvious that the latch disclosed herein could be used equally well witha single, slidable sash windo-w construction with either the keeperassembly or the latch assembly being mounted adjacent the closing edgeof the sash and the other assembly being mounted on the frame member ofthe window adjacent thereto. Additionally, this latch is not intended tobe limited solely to use in a window construction inasmuch as it isequally effective for tightly locking many other relatively movablepairs of elements together. Changes, therefore, in construction andarrangement 'may be made without departing from the spirit and scope ofthe invention as disclosed in the appended claims.

I claim:

1. In a device for successively latching and drawing together a pair ofrelatively movable sash members or the like into tightly locked edgewiseabutting'engagement, a latch mechanism comprising, a mounting plateattachable to one of the members adjacent the abutting edge thereof, acylindrical mounting pin secured to said plate and projecting normallytherefrom, said pin having an enlarged head portion at its outer end, acylindrical bushing having a longitudinally extending bore extendingtherethrough with the axis of said bore being disposed intermediate theaxis and periphery of said bushing, the bore in said bushing being of asize to receive said mounting pin whereby said bushing is freely andeccentrically rotatable on said pin intermediate said mounting plate andsaid enlarged head portion of said pin, an elongated locking leverhaving one end secured to said bushing for rotating the same relative tosaid mounting pin, knob means on the other end of said lever forrotating the same, an elongated latch arm having one end cylindricallybored and disposed about said bushing for free rotation relative to saidbushing and the locking lever secured thereto, hook means formed on theother end of said latch arm for latching engagement with a keeper pinmounted adjacent the abutting edge of the other relatively movablemember, and nger-engageable means on said latch arm for rotating saidlatch arm into latching engagement with the keeper pin when said bushingis in a rst position determined by said lever in which the center axisof said bushing is disposed between the keeper pin and said mountingpin, said bushing then being adapted to be rotated by said locking leverrelative to said hooked latch ann from said first position to a secondposition in which said mounting pin is disposed between the keeper pinand the axis of said bushing, the eccentricity of said bushing duringsaid rotation thereof by said locking lever between said first andsecond positions drawing the hook engaged keeper pin and said mountingpin toward each otherand providing a positive, over-center lockingaction for tightly locking the two relatively movable members inabutting engagement.

2. I-n a device for successively latching and drawing together a pair ofrelatively movable sash members or the like into tightly locked edgewiseabutting engagement, a latch mechanism comprising, ya mounting plateattachable to one of the members yadjacent the vabutting edge thereof, afinger-engageable flange projecting normally from vsaid mounting plateto facilitate movement of the Y member to which the latch mechanism isattached toward andraway from vthe other one of the pair of relativelymovable members, a cylindrical mounting pin secured to said plate andprojecting normally therefrom, said pin having an enlarged head portionat its outer end, a cylindrical bushing having anoff-center,'longitudinally extending, cylindrical bore formed thereinwith said bore having a Vdiameter approximately equal to the diameter ofsaid mounting pin, said bushing being fitted on said mounting pinintermediate said mounting plate and said enlarged head portion of saidpin for eccentric and free rotation relative thereto, an elongated latcharm having one end cylindrically bored and fitted over said bushing for-free rotation relative thereto, said latch arm having a hook formed atits other end whereupon said latch arm is adapted to be rotated intol'atched engagement with a keeper pin mounted adjacent to the abuttingedge of the other relative movable member when the main body portion ofsaid bushing is disposed toward .the keeper pin to latch the relativelymovable'members to each other, a nger-engageable flange projectingnormally from said latch member to facilitate pivoting said latch arminto and out `of latching engagement vwith lthe .keeper pin, anelongated locking lever having one :end fitted over and secured to saidbushing and having a iin'ger-.engageable knob `projecting from theopposite end thereof, said latch larm and said lever being freelyrotatable relative to each other, said lever being adapted to be rotatedwhen said latch arm is in'latched engagement Iwith the keeper pinbetween two positions whereupon said bushing is rotated relative .to theengaged latch arm until the main body portion thereof is disposed on`the side of said mounting pin away from the keeper pin, said rotationof said bushing drawing the hookengaged keeper pin and said mounting pintoward each other and providing a positive, over-center locking actionto tightly lock the two relatively movable members in abuttingengagement, and a resilient dished washer disposed on said bushingbetween said latch arm and said lever to permit non-binding operationVof the latch mechanism.

References Cited in the Iile of this patent UNITED STATES PATENTS

